1. Field of Invention
The present invention relates generally to apparatus and method of converting combustion energy into other useful forms of energy by the use of continuous concentrically rotating pistons in one direction, within a toroidal bore, said pistons transfer force through the outer radius of the present invention to a power shaft. This type of apparatus lends itself to energy conversion applications involving external as well as internal combustion. The present invention represents a significant improvement over previous similar types of apparatus.
2. Description of Prior Art
In rotary engines of this type, deflagration or externally combusted gasses or fluids have been used as motive force. Charges of hot gasses or fluids are introduced into the bore or in a separate combustion chamber, at timed intervals, behind the continuously moving pistons. A rotating disk, which performs the function of a head in conventional engines, serves to form a plurality of combustion chambers and as a wall for the expanding gasses to push against. When this type of engine is configured for internal combustion, means of inputting fuels has here-to-fore included either aspiration or use of a separate compressing means to force fluids into the combustion chamber.
In addition to rotary engines of the same type of the present apparatus, the ability to transfer combustion energy to other usable forms of energy is currently accomplished by at least three types of apparatus: the reciprocating engine, the Wankel engine and the turbine engine.
In a reciprocating engine the relationship of horsepower vs. fuel economy is influenced by the number and size of pistons. Each piston in a reciprocating engine must start and stop twice each crankshaft revolution. Referring to FIG. 1, the efficiency of transferring available cranking force 40 to the crankshaft varies sinusoidally as a function of the power transfer factor 41. Minimum power transfer factor 41 occurs at top dead center (the beginning of the power stroke, reference FIG. 1, 0 displacement) and at 180 degrees from top dead center (the end of the power stroke, 1.0 displacement). The maximum power transfer factor occurs near 90 degrees from top dead center (the middle of the power stroke, 0.5 displacement factor). The available cranking force 40 pushing on the piston is greatest at the beginning of the power stroke (0 displacement) and decreases as the piston displacement increases. Thus, the smallest percentage of energy transfer (smallest power transfer factor) occurs at the time when forces acting on each piston are greatest and least (1.0 and 0 displacement, respectively). Cranking force (delivered force) 42 delivered to the crankshaft of a reciprocating engine, during a power stroke, is substantially less than the available power 40 because of the sinusoidal power transfer factor 41 inherent in reciprocating engines. Actual delivered cranking force is less than the delivered force described in FIG. 1, because of constant linear piston and valve acceleration and friction in the reciprocating engine.
Wankel type engines use sets of two chambers. Combustion forces are applied to a geared rotor (piston) forcing it to travel about a center of rotation in an eccentric fashion. The rotational center of gravity of the rotor orbits about the center of rotation of the crankshaft causing an imbalance. This is somewhat offset by using additional rotors with their centers of gravity symmetrically located about their crankshaft. Imbalance along the center of rotation is still present because the rotors are not orbiting about a single point. At the beginning of the power stroke, the combustion forces are in line with the center of rotation of the crankshaft, resulting in no energy transfer at this point. This is also true at the end of the power stoke. Hence, the same type of power transfer inefficiencies discussed in the reciprocating engine are also present in the Wankel engine. The pistons (rotor surfaces) in the Wenkel engine are always accelerating do to the eccentric path the pistons follow.
The turbine uses expanding gases to push against slanted blades. Several stages of blades may be used to extract more energy from expanding gases. Force vectors causing rotary motion are approximately forty five degrees with respect to blade rotation and require stationary deflectors to redirect the flow of expanding gases. When forces are applied against stationary deflectors, energy is expended without being transformed into rotary motion. Two sources of wasted energy in turbines are: the angle of deflection of expanding gas pressure on rotating turbine blades and energy loss as gasses are deflected off stationary deflectors.